Underreamer



June 17,1930. 5 Q w ER 1,764,133

UNDERREAMER Filed Jan. 18, 1927 2 Sheets-Sheet 2 I N V EN TOR.

.E'mvm 6. W/s 'En BE)! 6. y 7 BY Patented June 17, 1930 UNITED STATES PATENT OFFICE EDWIN C. WEISGERBER, OF LONG BEACH, CALIFORNIA, ASSIGNOR '10 JOHN GRANT,

, 015 LOS ANGELES, CALIFORNIA UN DERRCEAMER Application filed January 18, 1927- Serial No. 161,758.

' This invention relates to a device for operating under the casing of a borehole for a well to enlarge the hole for the reception of the casing and the objects of the invention are to provide a simple andeflicient reamer for use particularly in oil wells by which the borehole may be uniformly enlarged and maintained in a straight'line, and in which the reaming members may be readily moved 7 to operative and inoperative position, as required. Another object of. my) inventlon is to provide a simple reamer y which the reaming or enlargement of a borehole may be accomplished diametrically as well as lonitudinally, without interfering with the proected position of the reaming members.

Other objects will appear from the following specification in connection with the accompanying drawings which illustrate a preferred embodiment of the invention and which it will be understood, is exemplary merely of a form in which the invention may .be embodied. 9

In the drawings,

Fig. 1 is an elevation, shown partly in section'on line 1-1 of Fig. 5, of a reamer embodying the invention, the cutters being shown in expanded position.

Fig. 1 is a View similar to Fig. 1, shown partly in section on line 11 of Fig. 6, the cutters being in contacted position.

Fig. 2 is a section on line 2-2 Fig. 1.

Fig. 3 is a section on line 33 Fig.1.

Fig. 4 is a plan section on line 4& Fig. 1

Fig. 5 is a plan section on line 5-5 Fig. 1, and

Fig. 6 is a plan section on line 66 Fig. showing the cutters in retracted position.

Referring particularly to the drawing and to the form of embodiment of the present improvement, my invention is shown as comprising a housing 1, reduced at the respective ends to form shoulders 2, and provided with a plurality of e ually spaced castellations or extensions 3, or purposes to appear later. Within the housing 1, and arranged for projection and retraction through lon 1- tudinal openings 4, by means presently escribed, is a pluralit of cutters or ream ng members 6 and 7, w ieh at their respective position and to inoperative or retracted position, as will appear later. Each'cutter or reaming member 6 and 7, is respectively pro-, vided with an arcuate cutting face 6 and 7 of any desirable design which will produce an eifective reaming of the borehole, and each cutting face 6 and 7" consists preferably of' a multiplicity of acuminate serrations which extend substantially in a horizontal plane, and which are provided intermediate the ends of the segmental cutters 6 and 7. The ends of the segmental cutters 6 and 7 are respectively provided with a plurality of vertical teeth 10 and 11, which function as milling cutters and which, as seen in Fig. 1, are outwardly rounding for the purpose of keeping the cutting faces 6. and 7 out of contact with the wall of the casing 12, during the in-' sertion in and withdrawal of the reamer from the casing, and also to cause the cutters 6 and 7 to be readily moved to retracted position Within the housing 1 when, during the withdrawal of the reamer from the reamed borehole, they are brought into contact with the bottom of the casing as will appear later. Each cutter or reaming member 6 and 7, respectively, is provided on each side with arcuate lateral flanges 13 and 14, Figs.

4,5 and 6, corresponding in outline to and arrange-d to operate against the inside of the housing 1 to prevent ingress of any of the drilling fluid and of cuttin s and other detrite during the operation 0 the reamer.

Theinner faces of said segmental cutters 6 and 7 are eccentric to the outer faces 6' and 7, and are provided with a plurality of longitudinal rollers 15 and 16, respectively, which are arranged to be held in place on such inner faces of the cutters by plates 17 and 18, suitably, but securely fastened in 1 position.

The inner faces of said cutters, that is to say, the roller carrying faces are arranged in contact with the faces of a plurality of cams 19 and 20, mounted, or provided on a a stem 21, the rotation in one direction of which operates tomove the cutters 6 and 7 outwardly. with respect to the housing 1 or to operative position, as shown in Figs. 4 and 5, and the rotation of which cam stem 21 in another direction operates to'move the cams 19 and, 20 whereby the movement of the cutters 6 and 7 to within the housing 1 I may be effected.

Each of the cutters 6 and 7 is formed on one side thereof with a longitudinal exten-,

reamer. .For this purpose, the respective ends of the cam stem 21 are squared, as at 21, Figs. 2, 3, 4, 5 and 6, and over the squared ends of said stem are fitted collars 22, which are externally threaded, and which are proor provided on the housing 1.

vided with a plurality of equally spaced peripheral recesses 22'for the accommodation of the castellations or extensions 3 formed By these collars 22, the housing 1 and cam stem 21, are rigidly interlocked, and the connection of the reamer as described with a drill pipe is effected by means of a cap 23, which is internally threaded and is arranged to be screwed onto the collar 22 and onto the externally threaded castellations 3 of the housing 1, whereby the parts so conjoined constitute a complete unit. The cap 23 is provided with the usual threaded extension 23 for connection with a drill pipe, not

' shown.

. cutters 6 and-7 being retracted during the descent of the reamer. through the casing. The reamer being then rotated, the cutting members 6 and 7 are caused to ride over the cams 19 and 20 and to be thrust outwardly beyond the housing 1, as shown in Fi s. 1 and 5. By this outward projection'o the cutters, the cutting faces thereof are caused to engage the wallof the bore and continuously to ream the borehole during the rota tion of the reamer. As the enlargement of the hole proceeds, the cutters 6 and 7, under the resistance offered by the material being cut, continue to move over the faces of thecams 19 and 20 until they reachthe limit of their outward thrust or travel, which occurs when the cutters strike the sides of the openings 4 and 4'.

When the reaming is completed, the drill stem is operated in a reverse direction, and this -o eration moves the cams 19 and 20 away rom theeccentric faces of the cutters 6 and 7, permitting the latter to assume the contracted positions shown in Figs. 1 and 6. By operation of the drill pipe, these cutters 6 and 7-may then be caused to ride over the cams in a reverse direction, and thereby to enter the housing 1, so that the cutting faces ing and normally extending into said open- I ings, said members provided at each end with m1ll1ng cutters, a stem extending throu h said housing and provided with means or causmg said cutters to move outwardly, means interlocking said housing and stem,

and means engaging said interlocking means and formed for connectionwith a dull pipe.

2. An under reamer comprising a housing, having rality of reaming members within said housing and extending into said openings, said members having means for limiting the outward movement thereof and provided at each end with milling cutters, a stem within said houslng provided with means for causing the cuttlng members to move outwardly and permitting same to move inwardly, collars on each end of said stem to interlock said housing and stem, and a cap fitting over one of said collars and having means therein for connection with a drill pipe.

3. An under reamer comprising a housing having longitudinal openings therein, a plurality of reaming members within said housing and provided with means for limiting the outward movement of said members, said members having milling cutters at the respective ends thereof, cam means within said housingto cause said members to move outwardly and permit same to move inwardly,

and means for interlocking said housing with said cam means.

longitudinal openings therein, a plu- 7 4. An under reamer comprising a housing having longitudinal openings therein, a plurality of reaming members within said hous 1 provided with a plurality of cams for causing said reaming members to move outwardly and permitting same to move inwardly, a collar on each end of said stem for interlocking said housing with said stem, and means engaging one of said collars and formed for connection with a drill ipe.

5. An under reamer comprising a ousin having longitudinal openings and provide at the ends thereof with spaced extensions, a plurality of reaming members within said housings and opera le through said openings, said members having means to limit the outward movement thereof, a stem within said housing provided with means for causing said reaming members to move outwardly and permit same to move inwardly, means for interlocking said stem and housing comprising externally threaded collars fitting over the ends of said stem and formed with recesses for accommodating the extensions of said housing, and means engaging one of said collars and having means :for connection with a drill pipe.

6. An under reamer comprising a housing, having longitudinal openings therein, a plurality of reaming cutters within said housin and arranged for projections through sai openings, said cutters being less in width than said openings and provided with flanges to prevent theingress of cuttings and the like into said housing during rotation thereof, cam means within said housing to cause said cutters to be moved outwardly and permit same to move inwardly, collars for conjoining said housing and cam means, and means engaging one of said collars and formed with means for attachment to a drill v 1 e. v p In an expansive reamer, an exterior housing with cutter receiving slots, an interior cam member fixed with relation to the housing, said cam member having thereon a radial cam, anda reaming member mounted in the housing slot in contact with thecam and movable in' the slot circumferentiallv about the cam and radially in and out through the slot.

8. In an expansive reamer, a tubular housing having a' slotted wall, a reaming member mounted in the wall slot, said reaming member being of such length as to substantially fill the slot in a lengthwise direction and be thereby held against relative lengthwise movement, but being of a circumferential length less than the circumferential length of the slot so as to be alwithin the slot, and a fixed cam member Within the housing having a radial cam with which the reaming member contacts and by virtue of which the reaming member is moved outwardly through the housing slot when it moves circumferentially with relation to the cam.

9. In an expansive reamer, a tubular housing having a slotted wall, a reaming member mounted in the Wall slot, said reaming member bein of such length as to substantially fill the slot ina lengthwise direction and be thereby held against relative lengthwise movement, but being of a circumferential length less than the circumferential length of the slot so as to be allowed relative circumferential movement within the slot, and a fixed cam member within the housing having a radial cam with which the reaming member contacts and by virtue of which the reaming member is moved outwardly through the housing slot when it moves circumferentially with relation to the cam, said reaming member having rings at both its circumferential ends to close the end portions of the slot.

In testimony whereof I have set my hand.

EDWIN O. WEISGEBBER.

lowed relative circumferential movenient 

